Fiber optic cables are useful for signal transfer. Light pulses representing data travel through the cables over very long distances and with great immunity to noise and other interference. However, fiber optic cables are more fragile than cables having electrical conductors. The fibers in the cable can be broken if the cable is bent beyond a certain amount. Once fibers are broken, signal transmission that is dependent upon those fibers terminates. Also, signal transfer in optical fibers is more susceptible to attenuation caused by bends in the fiber than is signal transfer through wires.
Typically, broken fibers and attenuation are not a problem in the median regions of the fiber optic cables. However, fiber at the ends of the cables can be troublesome because the cable must often bend where the connector attaches to a device. This is especially true when in confined spaces, such as when the device is mounted in a wall and the fiber connections to the device are made within the wall.
Ordinarily in walls, the fiber optic cable is routed parallel to the plane of the wall and within a gap separating panes of the wall. The fiber connections on the device are oriented perpendicular to the plane of the wall. Therefore, the cable must bend to account for the right angle between the direction of the fiber connector and the direction the cable is routed. If this bend forms a radius less than the minimum bend radius for the cable, a fiber break can result or the signal may become too attenuated for proper communication. For relatively narrowly gapped walls, a fiber break or attenuation is more likely to occur because the cable must form a bend with a relatively smaller radius.